Effects of different cycocel doses and irrigation levels on grain production, quality characteristics and water use in bread wheat

Abstract

Cycocel (CCC) is a synthetic substance widely used as a growth retardant in grain crops. The importance of CCC is greater under different stress conditions. In this study, the effects of different CCC doses (D0 = 0, D1 = 750, D2 = 1500, and D3 = 2250 g ha−1) and different irrigation levels (I0 = 100% as control, I1 = 75%, I2 = 50%, and I3 = 25%) on some agro-morphological characteristics, yield and quality parameters, and crop water use characteristics in a semi-dwarf bread wheat variety were investigated. The internode length, number of grains, grain weight per spike, biological yield and grain yield values showed significant reductions, especially under I3, regardless of CCC applications. Grain yields varied between 2.31-6.14 and 2.28-4.43 kg ha−1 in 2019-2020 and 2020-2021, respectively. There was no significant difference in crop water consumption among different CCC doses under the same irrigation level. The effects of increasing water stress on the decrease in plant height were greater than that of increasing CCC application. Under I3 and increasing CCC applications, the spike length was significantly reduced. The protein content, sedimentation, wet gluten ratio, and gluten index values increased significantly, especially under I2 and I3. Plant yield response factors for both biological (0.85-0.90 in 2019-2020 and 0.74-0.99 in 2020-2021) and grain yields (0.77-0.90 in 2019-2020 and 0.77-0.1.12 in 2020-2021) varied between years depending on CCC applications and climatic conditions. The foliar CCC application for the purpose of increasing crop yield during drought season might not be recommendable.